MBBT is regulated in Annex VI of the Cosmetics Regulation 1223/2009, ‘with the maxiuum concentration of 10% in cosmetic products such as sunscreens, day care products and skin lightening products'; its safety was confirmed in 1998 by the former structure of the committee, the Scientific Committee on Cosmetic Products and Non-Food (SCCNFP). In 2013, the SCCS assessed the safety of the nanoform of MBBT.

In this 2015 opinion, the SCCS has concluded that ‘the use of MBBT [2,2’-methylene-bis-(6(2H-benzotriazol-2-yl)-4(1,1,3,3-tetramethylbutyl)phenol)] in nano-structured form with the following characteristics as a UV-filter at a concentration up to 10% in dermally applied cosmetic products is considered to not pose a risk of adverse effects in humans after application on healthy, intact skin:

The material has a purity of ≥98.5% with the isomer faction not exceeding 1.5%, and the impurity profile not significantly different from that indicated in section 3.1.5.

The material has a median particle size (d0.5) of 120 nm or larger in terms of mass distribution, and/or 60 nm or larger in terms of number size distribution.

The material complies with other physicochemical specifications of the evaluated material as listed under section 3.1 of this opinion in terms of chemical identity, physical form, chemical composition, solubility, zeta potential, etc.'

The Scientific Committee nevertheless stated that ‘it is worthwhile to monitor possible irritation effects via the cosmetivigilance programs’. The committee also identified, potential long term bioaccumulation, and potential environmental effects to as concerns related to the use of this substance.

For previous NIA coverage of SCCS opinions on MBBT, please follow this link.